One of the great benefits of being let in on the Booker judges' advance thinking is that it enables you to consider candidates on the long list who probably won't make the cut, but undoubtedly deserve to. Andrew Miller's name doesn't have the heft of the big hitters (Kelman, McEwan, Naipaul); the ubiquity of the crowd-pleasers (Hornby, Bragg); or the perennial sympathy vote of Beryl Bainbridge. He's not even the fancied outsider (this year Philip Pullman).

I doubt he'll be unduly worried, however. Miller's debut, Ingenious Pain, won the IMPAC Dublin Literary Award - £54,000 more lucrative than the Booker - and the follow-up, Casanova, is being turned into a film. Both of these were historical epics, set in a lurid 18th century of the author's imagination; but for his third novel, Miller reaches back no further than 1997, the year of Hale Bopp and New Labour.

It reads like a deeply personal homecoming. Miller, a Bristol-born protégé of Malcolm Bradbury, creates a hero, Alec, who is a struggling, UEA-educated translator returning to his West Country childhood home. He is there both to confront his failure - his elder brother Larry is an ex-tennis star turned soap-opera celeb living the high life in San Francisco - and to care for his ailing mother, Alice, who sits amid the fading memories of her echoing house as cancer comes to claim her piece by piece.

Cancer is not a promising subject, yet Miller's evocation of the disease is both piteous and poetic. On the one hand, he presents Alice huddled in picnic blankets, "alien and wretched and smelling like a child's chemistry set". On the other, he suggests the infinite tenderness of the old woman asleep, "her inhalations like moments of hushed surprise; so that in each breath it seemed she lost more than she gained".

Miller ushers us to the heart of Alice's darkness. The image of night thickening behind the bedroom curtains, "pressing at the glass like floodwater", is reminiscent of Philip Larkin's great meditation on mortality, "Aubade", in which the poet desolately watches the curtain edges grow light, nudging death a day closer. Alice is not religious, but she cannot reconcile herself to the prospect that nothing will remain - that she is no more than "a brain that will die when the last of the oxygen was used up" -or that the afterlife is simply time spent in other people's memories.

Famously, Larkin suggested that what will survive of us is love. Miller is not so sure. He suggests that we should be judged by something weightier: by our "sudden tests of worth and courage - moments you say yes when others say no, or race back into the burning house without the least hesitation". To test this theory he introduces the parallel tale of Lásló Lázár, a Hungarian émigré playwright whose French script, Oxygène, Alec is translating.

Lázár seemingly has everything that Alec lacks - money, acclaim and a pleasant apartment in Paris, where he now spends his days writing obtuse Beckettian plays about the futility of action. A deep-seated sense of inadequacy grinds away at him, however, and gradually Miller's greater purpose is revealed. We learn that during the Hungarian uprising of 1956, Lázár, the famous dissident, failed to summon the courage that would have prevented the death of a lover.

The hero of Miller's debut novel was a surgeon who could not feel pain; the second featured a legendary seducer who could not get it up. Now he creates a revolutionary who could not pull the trigger. Most fiction catalogues its characters' achievements; Miller lingers remorselessly on their failures. It's a bleak world, but one invested with a peculiar beauty.